How to protect yourself from nuclear fallout (tips about radiation, building an expedient shelter, etc)

No one wants to think about a nuclear crisis – and hopefully it will never happen – but we all must accept the fact nuclear tensions are rising globally with North Korea (plus Iran, Al-Qaeda and others are seeking nukes) so we should prepare ourselves and our loved ones in the event the unthinkable strikes our soil.

For decades, movies and some in the media have portrayed a nuclear attack as a “doomsday” event implying most people would be killed on impact … and survivors would want to die once they come out of their shelters.

In reality, unless you are actually at ground zero or within a several mile radius of the blast zone (depending on the size of the nuke, of course), there is a very high probability you’ll survive as long as you…

limit your exposure to radiation and fallout,

take shelter with proper shielding, and

wait for the most dangerous radioactive materials to decay.

In other words, you CANsurvive a nuke attack … but you MUSTmake an effort to learn what to do! By learning about potential threats, we are all better prepared to know how to react if something happens.

Please realize this is being written with small nuke devices in mind (like a 1-kiloton to 1-megaton device). A larger device, ICBM or a nuclear war would cause more wide-spread damage but some of this data could still be helpful. These are some very basic tips on sheltering for any type of nuclear (or radiological) incident.

(Note: This topic is covered more in-depth in our IT’S A DISASTER! book, but these are some important steps that can help you and your loved ones survive a nuclear or radiological incident.)

The below graphic shows the destruction of a test home by an atomic blast on March 17, 1953 at the Nevada Proving Ground. The structure was located 3,500 feet from ground zero, and the time from the first to last picture was 2.3 seconds. It shows the force of the blast wave then the radiating energy set it on fire. (See more nuke test photos in our Fire in the Sky post.)

Also, if a nuke is launched over our continent and explodes miles above the earth, it could create an electromagnetic pulse (EMP). An EMP is a split-second silent energy burst (like a stroke of lightning) that can fry electronics connected to wires or antennas like cell phones, cars, computers, TVs, etc. Unless electronics are grounded or hardened, an area or nation could experience anything from minor interference to crippled power, transportation, banking and communications systems.

An EMP from a high-altitude nuke (where a nation or group succeeds in detonating a nuclear device carried miles into the atmosphere) could affect electronics within 1,000 miles or more as shown below. (Evidence suggests some countries and groups are working on enhanced and non-nuclear EMP weapons or e-bombs.)

What is the most dangerous part of a nuclear attack?

Both the initial nuclear radiation and residual nuclear radiation (also called radioactive fallout) are extremely dangerous.

Initial nuclear radiation is penetrating invisible rays that can be lethal in high levels.

Radioactive fallout (residual nuclear radiation) is created when the fireball vaporizes everything inside it (including dirt and water). Vaporized materials mix with radioactive materials in the updraft of air forming a mushroom cloud.

Fallout can be carried by winds for hundreds of miles and begin falling to the ground within minutes of the blast or take hours, days, weeks or even months to fall. The heaviest fallout would hit ground zero and areas downwind of that, and 80% of fallout would occur within 24 hours. Most fallout looks like grey sand or gritty ash and the radiation given off cannot be seen, smelled, tasted or felt which is why it is so dangerous. But as the materials decay or spread out radiation levels will drop.

More about radiation

Types of radiation – Nuclear radiation has 3 main types of radiation…

alpha – can be shielded by a sheet of paper or by human skin. If alpha particles are inhaled, ingested, or enter body through a cut, they can cause damage to tissues and cells.

beta – can be stopped by skin or a thicker shield (like wood). Beta particles can cause serious damage to internal organs if ingested or inhaled, and could cause eye damage or possible skin burns.

gamma – most dangerous since gamma rays can penetrate the entire body and cause cell damage throughout your organs, blood and bones. Since radiation does not stimulate nerve cells you may not feel anything while your body absorbs it. Exposure to high levels of gamma rays can lead to radiation sickness or death, which is why it is critical to seek shelter from fallout in a facility with thick shielding!

Radiation detection devices – You cannot see, smell, taste or feel radiation, but special instruments can detect even the smallest levels of radiation. Since it may take days or weeks before First Responders could get to you, consider having these devices handy during a crisis or attack since they could save your life.

survey meter – measures rate of exposure or intensity of radiation at that specific location if you stayed there for an hour … like a speedometer in a car (cost: $300-$1,000+)

dosimeter– a pen-like device you can wear that measures total dose or accumulated exposure to radiation as you move around (needs a charger too). Dosimeters cost about $45-$65+ each and some dealers offer 3 dosimeters + a charger for about $240 or so.

KFM kit – (Kearny Fallout Meter) measures radiation more accurately than most instruments since it’s charged electrostatically. Find plans online or available as a low-cost kit ($40-$75). And it’s a great science project for kids.

NukAlert – a patented personal radiation meter, monitor and alarm small enough to fit on a key chain. The unit warns you with chirping sounds if it detects radiation. (cost: $145 – $160)

RADTriage – postage stamp sized card (cost: about $20 ea)

Measuring radiation – Radiation was measured in units called roentgens (pronounced “rent-gens” and abbreviated as “R”) … or “rads” or “rem”. An EPA document called “Planning Guidance for Response to A Nuclear Detonation 2nd Edition June 2010” explains … 1 R (exposure in air) ≅ 1 rad (absorbed dose) ≅ 1 rem (whole-body dose). Although many measuring devices and older documentation use R and rem, officials and the media now use sievert (Sv) which is the System International or SI unit of measurement of radiation. The formula to convert sieverts to rems is quite simple … 1 Sv = 100 R (rem).

How many rads are bad? – High doses of radiation in a short span of time can cause radiation sickness or even death, but if that high dose is spread out over a long period of time, it’s not as bad.

According to FEMA, an adult could tolerate and recover from an exposure to 150R (1.5 Sv) over a week or 300R (3 Sv) over a 4-month period. But 300R (3 Sv) over a week could cause sickness or possibly death. Exposure to 30R (0.3 Sv) to 70R (0.7 Sv) over a week may cause minor sickness, but a full recovery would be expected. But radioactive fallout decays rapidly so staying in a shelter with proper shielding is critical!

The “seven-ten” rule – For every sevenfold increase in time after the initial blast, there is a tenfold decrease in the radiation rate. For example, a 500 rad level can drop to 50R in just 7 hours and down to 5R after 2 days (49 hours). In other words, if you have shelter with good shielding and stay put for even just 7 hours … you’ve really increased your chances of survival. Your detection devices, emergency radio or cell phone [if the last 2 are working, that is] can assist you in knowing when it’s safe to come out.

So how do I protect myself and my family?

Basic shelter requirements – Whether you build a shelter in advance or throw together an expedient last-minute shelter during a crisis, the area should protect you from radiation and support you for at least 2 weeks. Some basic requirements for a fallout shelter include …

distance – the more distance between you and fallout particles, the better

shielding – heavy, dense materials (like thick walls, earth, concrete, bricks, water and books) between you and fallout is best. Stay indoors or below ground. (Taking shelter in a basement or a facility below ground reduces exposure by 90%. Less than 4 inches of soil or earth can reduce the penetration of dangerous gamma rays by half.)

time – most fallout loses its strength quickly. The more time that passes after the attack, the lower the danger.

Indoor shelter locations – If you don’t have a fallout shelter, these options could provide protection from dangerous radiation by using proper shielding materials.

basement – find the corner that is most below ground level (the further underground the better)

1-story home / condo / apartment – if no underground facility, find a spot in center of home away from windows

trailer home – find sturdier shelter if possible (like a basement or brick or concrete building)

multi-story building or high-rise – go to center of the middle section of building (above 9th floor if possible). Note: if rooftop of a building next to you is on that same floor, move one floor up or down since radioactive fallout would accumulate on rooftops. Avoid first floor (if possible) since fallout will pile up on ground outside.

Shielding materials – All fallout shelters must provide good protection from radioactive particles. FEMA suggests having a minimum of several inches of concrete or 1 to 2 feet of earth as shielding around your shelter, if possible, and the more the better. Per FEMA, the following shows examples of shielding materials that equal the protection of 4 inches (10 cm) of concrete …

5 – 6 inches (12 – 15 cm) of bricks

6 inches (15 cm) of sand or gravel

7 inches (18 cm) of earth

8 inches (20 cm) of hollow concrete block

10 inches (25 cm) of water

14 inches (35 cm) of books or magazines

18 inches (46 cm) of wood

Make an expedient shelter – Some very basic ways to build an expedient last-minute shelter in your home, apartment or workplace to help protect you from dangerous radiation include…

Set up a large, sturdy workbench or table in location you’ve chosen. If no table, make one by putting doors on top of boxes, appliances or furniture.

Put as much shielding (e.g. furniture, file cabinets, appliances, boxes or pillowcases filled with dirt or sand, boxes of food, water or books, concrete blocks, bricks, etc.) all around sides and on top of table, but don’t put too much weight on tabletop or it could collapse. Add reinforcing supports, if needed.

Leave a crawl space so everyone can get inside and block opening with shielding materials.

Leave 2 small air spaces for ventilation (about 4-6″ each) – one low at one end and one high at other end. (This allows for better airflow since warm air rises.)

Have water, radiation detection devices, KI, battery operated radio, food and sanitation supplies in case you have to shelter in place for days or weeks.

In summary, those within the blast zone of Ground Zero (depending on the size of the nuke) won’t make it .. BUT .. if you are a few miles outside the zone your chances of surviving it are high but you MUST have detection devices to monitor levels of radiation and a plan to stay sheltered for at least 48 hours or up to a few weeks. First Responders will have to wait for the deadly fallout to decay before they enter a hot zone so the more you prepare, the better your odds of surviving a terrorist nuke.

As mentioned earlier, our 266-page IT’S A DISASTER!book explains more about nuclear incidents and many other disasters, emergencies and basic first aid … and we discount our $14.99 paperback down to $4.50 US each (on 10 or more copies) or PDF ebook is only $3 US. Plus we customize our products for free.

Learn more at www.fedhealth.net or call Fedhealth at 520.907.2153 (7a-4p Pacific M–F) for more information.

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45 Responses to How to protect yourself from nuclear fallout (tips about radiation, building an expedient shelter, etc)

Hmm it seems like your site ate my first comment (it was super long) so I guess I’ll just sum it up what I submitted and say, I’m thoroughly enjoying your blog. I as well am an aspiring blog blogger but I’m still new to everything. Do you have any recommendations for novice blog writers? I’d certainly appreciate it.

Doing windows may help a little but realize if there’s nuclear fallout piling up outside, you want to get as much shielding around you as possible to help protect from penetrating gamma rays / radiation. I didn’t include this in original post but for example (from our book)…

Shielding materials – All fallout shelters must provide good protection from radioactive particles. FEMA suggests having a minimum of several inches of concrete or 1 to 2 feet of earth as shielding around your shelter, and the more the better. Per FEMA, the following shows examples of shielding materials that equal the protection of 4 inches (10 cm) of concrete …
• 5 – 6 inches (12 – 15 cm) of bricks
• 6 inches (15 cm) of sand or gravel
• 7 inches (18 cm) of earth
• 8 inches (20 cm) of hollow concrete block
• 10 inches (25 cm) of water
• 14 inches (35 cm) of books or magazines
• 18 inches (46 cm) of wood

As fyi, a free ebook you might want to check out on OISM site is “Nuclear War Survival Skills” by Cresson Kearney at http://www.oism.org/nwss Thanks for stopping by! j

Hi Krystal and I’m sorry – I got sidetracked with a project and meant to come back here last night to reply. Our next blog post (what I worked on yesterday and wrapping up today) will address your questions since it discusses some things happening at Fukushima as we speak.

Is the fallout something to worry about .. if near the emitting source – yes because concentrations are so high – esp the contaminated water spewing from leaky tanks, overflows, etc so Japanese officials / people should continue to monitor things closely.

But how much of it will impact aquatic life is the big question many official and experts can’t agree on. Would we personally eat seafood or kelp from Japan / Asia at this point .. probably not esp due to Bill’s health issues. And as contaminated water moves / settles across the ocean radioactive particles will dissipate / decay since time & distance help reduce radiation levels … but since there is strontium and cesium involved (which both have much longer half-life = slower to decay) .. there are some concerns up and down the west coast of North America — altho some say it will be so diluted it won’t harm. But we probably won’t know until it starts to arrive. (sigh)

One thing you might want to consider for your personal kits is including some type(s) of device(s) to monitor air and objects. (See section on radiation detection devices above.)

I know this reply doesn’t really answer your questions but stay tuned and read our next post since it may help put some things in perspective (and/or curl your hair) .. and thanks for your input and patience. stay safe, j & B

As mentioned above, several inches of concrete (and other substances) can protect you from gamma rays during a nuclear disaster, and during such an event (esp with fallout present), people need to decontaminate themselves before entering a shelter if exposed.

EPA explains most people’s primary source of gamma exposure is naturally occurring radionuclides, particularly potassium-40, which is found in soil and water, as well as meats and high-potassium foods such as bananas. Other sources affect people who live near certain types of mines or regions (esp. uranium) and nuclear medicine (e.g. scans, etc) contributes to the total, so you’re correct .. we’ll never completely eradicate it from our environment since radiation is everywhere.

And personal dosimeters and/or survey meters could measure and monitor alpha, beta and/or gamma levels if concerned about levels in your environment. But realize many radionuclides can be cleared via the urine or feces so it’s always good to flush and detox internally to keep things moving.

What’s Happening i am new to this, I stumbled upon this I’ve
discovered It positively useful and it has helped me out
loads. I’m hoping to give a contribution & aid other customers like its
helped me. Good job.

What a stupid load of information all that was.
The chances of surviving a nuclear attack are nil in any sense of the word.
During the 2nd world war a bomb was dropped on nagasaki and hiroshima the japanese had no means to retaliate.
Today is a different story every major country has them and they all want to kill each other
and if one fires they will do just that.
Within 30 minutes part of the world will be lifeless, all water will be contaminated so will food fields animals,there will be no emergency help no police no nothing im sure everyone has seen 3 mile island. Chernobyl from which people are still dying as a result of
Even through europe. But we can put it down to smoking ,we dont want to piss the russians off by putin a claim in….
imagine 20 nuclear warheads were to land in england at strategic points on a monday
When most are at work. You have 8 minutes
From launch 85% of the country wouldnt even know before they were dropping so while you have a few seconds to spare try to think will i have enough time to get to my bunker. … you know the answer. And the products you are trying to sell will not help while your skin is dripping from the bone …stop watching stupid films and reading stupid articles

Wow … while we appreciate all input and comments your statement “the chances of surviving a nuclear attack are nil…” is not accurate.

Also … we prefaced this article with a paragraph where we wrote … “Please realize this is being written with small nuke devices in mind (like a 1-kiloton to 1-megaton device). A larger device or a nuclear war would cause more wide-spread damage but some of this data could still be helpful. These are some very basic tips on sheltering for any type of nuclear (or radiological) incident.”

Yes .. a global war with ICBMs would cause mass death and destruction along with a nuclear winter, however for decades a vast majority of nuclear nations have had an informal “MAD” (mutually assured destruction) understanding. In other words if you attack us, we would attack you virtually simultaneously, and the end result would be a destruction of both countries.

But as we all know there are certain countries and groups who don’t have the technology yet but are seeking it aggressively, and many of those weapons would probably be smaller devices as mentioned above.

And obviously (as we stated above) if someone is within a few mile radius of ground zero of a small nuke device they’re not going to make it. But … people further away CAN survive but they MUST take shelter and stay shielded for at least 48 hours or up to a few weeks until the deadly radiation levels have decreased.

The only product we “sell” is our customizable disaster preparedness and basic first aid book that many local, state and federal agencies, nonprofit groups, and corporations give to their employees and local communities around North America. But we GIVE a lot of the information away for free through our blog and website since our goal is to help educate the public and hopefully help save lives.

I encourage you to please visit some of the following sites (which are just a few of the many resources used when assembling data for the nuclear topic)…

there will be a ww3. All the details are there. If you look deeply into Russian Secure DB’s there are plans. Plans to wipe certain cities in certain countries. I’m just giving a heads up, we managed to intercept a secure email and the soonest day would be in 2017.

To survive nuclear fallout, you must have shelter. Look for dense materials such as concrete, earth, bricks, books, or water. In case of a bomb blast, the best place to be is a basement. Plan to stay there for at least 2 days. For more tips, click here.

What if you live 50-100 miles from the nearest major city that would be hit, I’m sure the variables are high, but how much fallout should be expected? Insofar as a ratio over distance traveled. Also, what about a protective suit? Is there anything that protects well enough to be outside within the first couple days? And how much is needed to fend off residual fallout after levels have dropped? Would a basic gas mask work or is something else needed? Lastly, say it was a Russian warhead 50 miles out, would the overall procedure need to change?

The amount of fallout really depends on size of the nuke. Above blog and several comments here describe things to do in the event of a small 1 kiloton to 1 megaton device, but some ICBMs can be as large as 25+ megaton which would create much more fallout. As fallout spreads out in atmosphere it will decrease in intensity due to winds and time, but could potentially be carried for hundreds of miles (again, depending on size, wind patterns, etc.)

There are various types of protective suits, gas masks, detectors, and other hazmat PPE … but even with that on it is NOT worth venturing out during first few days. First responders won’t be allowed into hot zones for at least 48 hrs to 2 weeks or more (depending on event) – esp. since you cannot feel, smell, taste or see dangerous radiation. Radiation detectors can help but they must be calibrated and people need to know how to use them, so the best thing to do during any type of nuclear incident is to shelter in place for at least 48 hours (or possibly up to 2 weeks or more) to ensure the deadly fallout has decayed. (See above “seven/ten rule” in blog). And anytime someone does venture out they need to remove clothing, hats/hoods, gloves, etc. outside so they don’t contaminate the shelter or others. Rinsing off (esp hair) is also wise if possible but key is to keep outside elements and radiation out of shelters as best as possible.

As far as a Russian warhead 50 miles out, again the size of payload (KT versus MT) would determine how many miles out might be affected. There is a widget by Carlos Labs called “Ground Zero II” where you can put in a city, use the drop down menu to choose size of weapon/warhead, then click on thermal, pressure & fallout map buttons to see projections at http://www.carloslabs.com/node/20

Some other helpful resources (which are just a few of the many we used when assembling data for the nuclear topic) are…

Hi Travis. I’m not an expert by any means but I have found some resources that may be of help. http://nuclearsecrecy.com/nukemap/ will allow you to drop a nuke of varying size at a desired location and see the results of surface or air burst. The short answer to your ‘how much fallout’ question, is it depends which way the wind is blowing, if its a surface or air burst and how big the nuke is. I believe that new Russian Sarmat 2 delivers up to 10 stealth warheads each of up to 40Mt from a single missile, but I dont think its ready yet. My understanding is a gas mask will filter radiation contaminated air particles from entering your lungs and a NCB suit will stop the particles from actually touching your skin. However, It wont stop the gamma radiation from actually penetrating through. If you survive the blast, you need to take enough food and water to your shelter (or prepare early) and stay covered for weeks.

Great tips David thank you … and no – I didn’t block your reply but did respond to Travis before I saw & approved your comments. If you read our blog and several of my replies to above comments you & we are both saying similar things since we are both correctly stating the issues and concerns. Thanks again for your input and for stopping by.

We are exposed to gamma rays from natural environment plus rays are produced for use in the scientific, medical, industrial applications as well as in the food industry. In the case of a nuclear device, there could be some impact to the agriculture industry (including gardens) in the hot zone which is why it is important to have stored foods and water in a shielded environment.

That said, according to “Nuclear War Survival Skills” …

“Myth: So much food and water will be poisoned by fallout that people will starve and die even in fallout areas where there is enough food and water.

Facts: If the fallout particles do not become mixed with the parts of food that are eaten, no harm is done. Food and water in dust-tight containers are not contaminated by fallout radiation. Peeling fruits and vegetables removes essentially all fallout, as does removing the uppermost several inches of stored grain onto which fallout particles have fallen. Water from many sources — such as deep wells and covered reservoirs, tanks, and containers — would not be contaminated. Even water containing dissolved radioactive elements and compounds can be made safe for drinking by simply filtering it through earth…”

Nuclear is just a disaster is there any way that we come to treaty where no one in world sud use Nuclear.
only 5% of people maybe survive if they have proper shelter. rest will be all expose to Gamma rays and we cudnt produce anything from affected city or area.

Hi 62martian. I’m not aware of any specific group (altho there probably are some out there) but I do know APN has a map on their forum’s home page with links to “Prepper Meetup groups” over at http://americanpreppersnetwork.net/ . You also might want to snoop thru your state’s subforum over there too and possibly the Disaster Preparedness subforum. Hope this helps and thanks for stopping by.

Hi Lynn and my apologies for delay in responding. If the water [and tote] is stored indoors, you probably won’t have to worry about fallout getting in it like you would using water from outside sources like wells, ponds, lakes, etc. That said, if you’d like to learn more about expedient settling and filtration methods to remove fallout particles and most of the dissolved radioactive material, visit http://www.oism.org/nwss/s73p919.htm Thanks for stopping by!

So…here we are with North Korea looming larger than life. The kitchen of my doublewide mobile home can be rapidly fortified into a fallout shelter, but what can I do about the roof and skylight? From ceiling to rooftop is 10″ of space with insulation and A/C vent tubing. The roof is shingled. Any suggestions would be appreciated, though hopefully not needed. Thank you for the valuable information.

My apologies for delay in responding Catsablanca … and you’re right – the main thing during first few days would be the potential fallout accumulating on your roof/skylight. One possible suggestion is if you pull a large sturdy table into kitchen, you could stack shielding materials (mentioned in above post) on top and all sides to help protect you from accumulated radioactive fallout. Shane Conner has some good tips in his free guide at http://www.ki4u.com/guide.htm

As mentioned in 1 of the above comments, all fallout shelters must provide good protection from radioactive particles. FEMA suggests having a minimum of several inches of concrete or 1 to 2 feet of earth as shielding around your shelter, and the more the better which is why basements are great for sheltering. Per FEMA, the following shows examples of shielding materials that equal the protection of 4 inches (10 cm) of concrete …
• 5 – 6 inches (12 – 15 cm) of bricks
• 6 inches (15 cm) of sand or gravel
• 7 inches (18 cm) of earth
• 8 inches (20 cm) of hollow concrete block
• 10 inches (25 cm) of water
• 14 inches (35 cm) of books or magazines
• 18 inches (46 cm) of wood

So you could place boxes filled with sand or dirt, books, water, etc. around all sides and on top of sturdy table and hunker down for several days. See Expedient shelter tips in above original post or consider other shelter options mentioned in Kearny’s NWSS book at http://www.oism.org/nwss/s73p916.htm

Thanks for stopping by and hopefully it’s not anything we’ll have to deal with but glad people are thinking about ways to prepare for such a possibility. Stay safe out there, j & B

I’m a Radiation Tech, and yes you maybe able to survive a Nuclear Attack depending on the size and how many missels are launched. My theory is also depending what Isotope is used. Not only gamma rays might kill you but also beta atmitters who can get to your tissues, depending on what they are using. The only chance for survival is going deep under ground like a silo. Also not mentioned in this report is the side of the human nature and trying to survive. Food source and water source will be compromized. There is no survival if we go into WWIII mode. Sorry for the bad news so stay safe and be prepared becuase we will all need it.

Correct and thank you for your input. We did preface post with note saying it was being written with small nuke devices in mind (like a 1-KT to 1-MT device), and you are right about the isotope, as well as going deep underground (which we mention above). We do go more in depth about food and water and provide many links to resources in our Nuclear topic in our 266-pg preparedness & first aid book. It was tough to create a blog post from a 17-pg nuke topic but we tried to hit some key points like limit exposure to radiation, take shelter with proper shielding, and wait for the most dangerous radioactive materials to decay, as well as encourage people to get detection devices, understand 7/10 rule, tips on expedient shelters, etc. Thanks again for taking the time to share your expertise and hopefully we won’t experience WWIII mode anytime soon. Take care, j

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I never knew that areas downwind could cause so much devastation. I can see how having a bomb-sniffing dog would be helpful for detecting a bomb early. I’ll have to consider your tips so that I am not exposed to radiation.